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Application of Predictive Maintenance System in Drinking Water Pumping Stations

100%
Kiliç R., Kozan R., Karayel D., Özkan S.
Acta Physica Polonica A
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2017
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vol. 132
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issue 3
1016-1021
EN
Pumping stations are some of the most important facilities of water administration. Continuous operation of these facilities is of utter importance, to be able to serve at all times. Maintenance of these facilities is also crucial for uninterrupted operation. In this study, the functioning of the predictive maintenance technique, which is based on the vibration analysis, is briefly addressed, and the application of the technique in a real system is presented. In the real system, the steps that must be done in order to apply this system are shown step-by-step. At the end of the study, the failures determined by using the predictive maintenance method are analyzed, and solution suggestions are presented.
2
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Effects of Material Non-Homogeneity and Two Parameter Elastic Foundation on Fundamental Frequency Parameters of Timoshenko Beams

80%
Avcar M.
Acta Physica Polonica A
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2016
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vol. 130
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issue 1
375-378
EN
In the present study, effects of material non-homogeneity and two-parameter elastic foundation on the fundamental frequency parameters of the simply supported beams are examined. Material non-homogeneity is characterized taking into account the parabolic variations of Young's modulus and density along the thickness direction of the beam while the value of Poisson's ratio is assumed to remain constant. The foundation medium is assumed to be linear, homogeneous and isotropic, and it is modeled by the Pasternak model with two parameters for describing the reaction of the elastic foundation on the beam. At first, the equation of the motion including the effects of the material non-homogeneity and two-parameter elastic foundation is provided. Then, the solutions including fundamental frequency parameters versus various non-homogeneity, density and foundation parameters, and length to depth ratio adopting the Timoshenko beam theory as well as the Euler-Bernoulli beam theory are presented. To show the accuracy of the present results, a comparison is carried out and a good agreement is found.
3
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Analytical Determination of the PZTs Distribution in Active Beam Vibration Protection Problem

70%
Brański A., Lipiński G.
Acta Physica Polonica A
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2011
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vol. 119
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issue 6A
936-941
EN
The paper concerns an active vibration protection (p-reduction) of the structure via piezoelectric transducers; p-reduction corresponds to an active vibration reduction (a-reduction). The quantity and effectiveness of the (a- or p-) reduction, among other parameters, depend on the piezoelectric transducers distribution on the structure. The best results are obtained bonding piezoelectric transducers to the structure in the sub-domains with the largest curvatures; it is so-called quasi-optimal distribution of the piezoelectric transducers. Up to now, the quasi-optimal distribution was determined based on heuristic reasons only. The aim of the paper is to confirm quasi-optimal distribution in analytical way. The beam clamped at one end, vibrating with first three modes separately, is chosen as the research object. It is assumed that the piezoelectric transducers are exactly the same. Demanding the vibration amplitude to be equal to zero (i.e. p-reduction condition), the general formula for interacting forces piezoelectric transducers-beam is derived. Next, such an appropriate distribution of piezoelectric transducers is searched analytically, that the minimal forces are achieved; it leads to the best reduction effectiveness. It turned out that the analytical method pointed out quasi-optimal distribution of the piezoelectric transducers. The validation of theoretical considerations is confirmed numerically.
4
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Effectiveness Analysis of the Beam Modes Active Vibration Protection with Different Number of Actuators

61%
Brański A.
Acta Physica Polonica A
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2013
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vol. 123
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issue 6
1123-1127
EN
This paper deals with an active vibration protection (p-reduction) of the beam-actuators mechanical system, hence it concerns separate modes. The paper's aim is an effectiveness analysis of the p-reduction assuming different number of actuators. It is assumed a priori that actuators are bonded to the beam in the sub-domain with the largest curvatures and they are exactly the same. The beam clamped at one end is chosen as the research object. Next, as required by the p-reduction condition, the number and distribution of actuators are changed. It turns out that the best reduction effectiveness, measured via any effectiveness coefficient, is obtained for one actuator bonded in the sub-domain with the largest curvature. The validation of theoretical considerations is confirmed numerically.
5
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Analytical Determination of Optimal Actuators Position for Single Mode Active Reduction of Fixed-free Beam Vibration Using the Linear Quadratic Problem Idea

61%
Żołopa E., Brański A.
Acta Physica Polonica A
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2014
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vol. 125
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issue 4A
A-155-A-158
EN
An analytical solution is obtained, based on linear quadratic problem well-known in the control theory. The problem is formulated for fixed-free beam vibration (fourth order partial differential equation) in Hilbert space and the point control and distributed output is considered. Beam deflection at any point is chosen as a criterion of optimization. In this case it means the linear quadratic problem. Up to now, the linear quadratic problem was formulated many times, but only for the time-dependent equation. The aim of the paper is to obtain the value of the cost functional formulated as the function of distribution of actuators. The minimum of this function leads to the optimal actuators location. The results obtained with this method confirm the results obtained in heuristic way and pure analytical one for separate mode; it is pointed out that the actuators ought to be bonded on the beam sub-regions in which the mode curvatures take their local maximums and the highest value.
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